Connector for electric cables



March 30, 1965 M. cox-:N 3,176,258

CONNECTOR FOR ELECTRIC CABLES Filed Aug. 24, 1960 27 Zeig/@ 22\ MAW/NCwNTOR wwf/WMM United States Patent O 3,176,258 CONNECTOR FOR ELECTRICCABLES Martin Coen, 738 Sea St., Quincy, Mass. Filed Aug. 24, 1960, Ser.No. 51,693 9 Claims. (Cl. 339-42) ,due to the heat generated inconnections where the resistance is not extremely low. In the past ithas been f the practice to braze or weld such cable junctions to keepthe resistance within reasonable limits. An operation of this sort,however, is both expensive and time consuming.

Another disadvantage to prior art connectors is that mest aremanufactured as male and female mating pairs. Since the male and femalemembers are specifically adapted for engagement with the oppositevariety, and generally do not mate with members of the same variety, itfrequently becomes necessary to change varieties on a given cable end inorder to make the desired interconnections.

It is an object of this invention, therefore, to provide an improvedconnector which avoids one or more of the disadvantages of the prior artconnectors.

lt is a further object of this invention to provide an improved, highcurrent carrying capacity connector capable of mating with connectors ofsimilar kind.

Yet another object :of the present invention is to provide an improvedconnector which maintains a low contact resistance after repeated usage.

An additional object of the present invention is to provide an improvedconnector which is not readily subject to short circuiting when not inuse.

In accordance with the inventon, the connector comprises a conductivesleeve adapted for engagement with a cable end and terminated in apredetermined configuration. A means is provided for electrically andmechanically securing the sleeve to the cable end. A retractable, springbiased jacket surrounds the sleeve and is adapted simultaneously toprovide insulation of and tension on a connection `formed between theconnector and one of similar kind.

For a better understanding of the present invention, together with otherand further objects thereof, reference is made to the followingdescription taken in connection with the accompanying drawings and itsscope will be pointed out in the appended claims.

In the drawings:

FIGURE l is a perspective view, partly in section, of an embodiment ofthe present invention illustrating a connection formed therewith.

FIGURE 2 is an enlarged elevational section of the embodiment of FIGUREl, and,

FIGURE 3 is a perspective view, exploded and partly in section, ofanother aspect of the embodiment of FIG- URE l.

Referring to FIG. 1 of the drawing there is shown an electric cable 2Qand a pair of similar connectors 2l and 22 embodying the invention. Theelectric cable 20 comprises a stranded conductor 23 and insulation 2d.The insulation 24 is bared from the cable end which is enclosed by thesleeve 25. The sleeve 25 is adapted for engagement with the bared cableend by means of the split ring 26 carried within the sleeve 25. At thispoint the cable end is surrounded by a band of foil 26a to H6258Patented Mar. 30, 1965 prevent the split ring 26 from cutting the cablestrands. At one end, the sleeve 25 is terminated in a predeterminedconfiguration as, for example, the terminal 27. Encasing the sleeve 25and part of the cable 20 is a retractable, spring biased insulatingjacket 28. Illustrated more in detail in FIG. 2 is the insulating jacket28 and its relation to the cable 20 and the sleeve 2S. From this figureit may be seen that the sleeve 25 is rmly secured to the cable end bymeans of the outer ring 29 which is concentric with the inner ring 26.This ring 29 also acts as a shoulder against which the bias spring 30 isurged when the jacket 28 is pulled back to expose the terminal 27. Theother end of the bias spring 30 is restrained by means of the shoulderor offset 31 in the jacket 28. Disposed radially through the terminal 27is a knockout pin 32 against which the shoulder or offset 3i rests whenthe bias spring 30 is fully expanded. Knockout pin 32 is, for example,longer than the diameter of the terminal 27. This not only enables it toprevent undesired removal :of the jacket 28, but also provides a meansfor selectively restraining the jacket 28 in a retracted positioncompressing the bias spring 30 and exposing the terminal 27. To performthis latter function the jacket 2S is provided with axial grooves 28aextending from the shoulder 31 to the opening of the jacket 23. The pin32 is, therefore, restricted to axial motion in the grooves. If thejacket 28 is pulled back sufciently far, the pin 32 will be exposed.When the pin 32 is thus exposed, the jacket 28 may be rotated so the pin32 can no longer engage the grooves and the jacket 23 will be restrainedin this retracted position. It is to be particularly noted that theterminal 27 is of a configuration that facilitates its engagement with aterminal of similar kind. Male and female terminal variations are notused, nor are they ever needed.

The installation and operation of the connector of the present inventionare simply performed without the use of special tools. The sleeve 25 isfor example, split so that it may be opened slightly to receive thebaredend of the cable 20. When the bared cable end is inserted into thesleeve 25, the outer ring 29 is slipped over the terminal 27 and forceddown the sleeve 25 until it is in register with the inner ring 26. Thiscauses the inner ring 26 to bite down into the cable end simultaneouslyto provide a secure mechanical and electrical connection of the sleeve25 to the bared cable end. Since the resistance of the connectiondepends upon the surface area of contact and the quality of the contact,the arrangement justdescribed provides an excellent connection of lowresistance Without the need of welding or brazing. Tremendous contactforces are achieved by the outer and inner ring arrangement illustrated.

As previously pointed out, the jacket 28 may be pulled back to exposethe terminal 27. When this is done, the terminal 27 may be placed intoengagement with the terminal of a connector of similar kind. Uponrelease of the jacket 2S, it will spring back and simultaneously provideinsulation of and tension on the connection thus formed.

Release of the connection, accomplished in the manner just described, islikewise effected by retracting the jacket 28 to expose the terminals27. The tension on the joint may be relieved by rotating the jacket y28and restraining it against the pin 32. Rotation of the jacket 28 onceagain after separation of the connection permits the pin 32 to engagethe grooves and the jacket 28 to spring back beyond the terminal 27 Thislatter position of the jacket 28 has the additional unique feature ofpreventing inadvertent short circuiting of the cable.

Another aspect of the embodiment of FIG. l is shown in FIG. 3. Herethere is illustrated a connector of similar kind comprising a terminal33, corresponding in configuranon to the terminal@ offresi and 2.vExtending,f1-em .f

,j 3,176,258 j 'I the terminal 33 is a threaded stud 34. The threadedstud 34 into the sleeve 35 until suiiicient'pressure is vbrought to inthe insulating'jacketd. The jacket S6 may, forlex-y ample, have afradialhole disposed therein suitable for the insertion of a welding rod, notVshown. The welding rod,

Awith an identical terminal,y the other, end oi'said sleeve being splitso asto be compressible about a' cable disposedwithin it, means disposedaboutr the sleeve for compressing it on an Aelectricaly cable, meansdisposed inthe sleeve atfitsV split end for mechanicallygrippin'g thecable when the splitv end ofthe sleeve iscompressed, an insulatnotshown, is then secured =by Vmeans of screwing the stud 34 into thesleeve 35 until'suicient pressure is brought to@ bear upon 'the WeldingVrod to Vestablish good yelectrical contact as well as firmk mechanicalengagement. e

The present invention provides a significant step forward in theelectrical connector art byeliminating the vuse of f,

male and female type connectors and providing a connec#` tor whichhasjhigh current carryingcapacity, is capable,

of mating with connectors of similar kind Yandi-which cannot beseparated fby axial movement. Y Y

While there have been described what are at present considered to be thepreferred embodiments of this'in-v i vention, it Will -be obvious tothose skilled in the art 'that various changes and modifications maybemade thereinY without departing from the invention, and it is,therefore,

aimed in the appendedclaims to cover all such changesY ingjacketsurrounding the sleeve and biased to a position wherein it'extendsover the fterminal, and means ncluding 'aV pin and slot ,assemblyvformed on the sleeve and jacket for retaining the jacket in a retractedposition wherein it yexposes `the terminal.

5.A connector as delined Vin clai1n4 further character- Yized byysaidmeans disposed about the sleeve including .a ring alignedfwith'themeans disposedin the sleeve.

and modifications asfall within the truespirit andscope of theinvention.

What is claimed is:

A1. In a connector for electric cables said connector h'aV-y ing aninsulating jacket, theifmprovement comprising a conductive sleevedisposed within said jacket and adaptedY to receive a cableend, a splitin the Wall of said sleeveenabling said sleeve to be compressedy aboutthe cable end,

a split ring disposed within said sleeve in the'region ofthe l split,andan outer ring positioned concentrically about sleeve, and meanssurroundingsaid sleeve and within theY jacket recited below forcompressing said split ringen. the v cable end; va springvbiasedretractable jacketsurroundingV said sleeve and adapted simultaneously toprovide insulatingof and tension on a Aconnection formed betweensaidconnector and one of a similar kind, said retractable jacketextendingnormally beyond said cableend and sleeve and adapteduponretraction to expose the-part of said sleeve said sleeve in theregion of .the split forgcompressing said v Y to esta'blishV elecingmeans for the jacket.

6. A connectorA as deinedin claim 5 fur-ther charactery ized by saidring providing a-stopibetween the jacket and (the sleeve, Va shoulderformedV on the innersurface of the jacket providingrasecond stop betweenthe jacket andthe sleeve, and a spring disposedbetw'een the'jacket andthe sleeve and engaging the ringand shoulder providing a bias- 7.A'fconnector as defined in, claim'S vfurther characterized by a seatformed in thev outer `surface of .the sleeve receivingthe' ringandrrestraining the ring againstfaxial movement on 4the sleeve.

8. A connector Vfor cables comprising a sleeve made yof electricallyconductive material and having splits therein to facilitate compressionofthesleeve,r a ringv disposed within the sleeve at `the location ofthe'splits and adapted to engage and grip a bared cable when the lsleeveis compressed about it, a second ringfsurroundingthe first recited ringand disposed outside Ithe, sleeve, a generally hook shaped terminal atone endofV-thejsleeve adapted to matewith an videntical terminal, aninsulating jacketv surrounding the sleeve andA having an'inwardlylextending shoulder in the vicinity ofthe terminal, and Y.a coil rspringdisposed within the jacketand aboutthe sleeveengaging the shoulder atone endand the secondring lat the other, said springbiasingfthe jacketyto a position wherein it surrounds the terminal.V Y

Y l 9. A connector as defined in claim Sfurther characterized by a pincarried yby the sleeve and anaxiallydirected groove inthe jacket, saidpin riding inthe groove and terminatedinthel predeterminedconfigurations; an axially directed groove in said jacket, a pin mountedon and eX-` tending radially from said sleeveY and adapted to move inthe groove upon retraction `of said jacket and means for preventing saidpin from entering said .groove :when said jacket is in its retractedposition to restrain said jacket in said position.- y I Y 3. A connectoras deined'in claimy 2 further characterized'by the means -forcompressing said split ring on the cable end including an outer ringpositioned concentrically.V f

about said sleeve and aligned radially with the splitring.

4. A connector for electricalcables comprising a sleeve y made ofelectrically conductive material adapted to receive the bared end of aneletcrical cable, a hook-like terminal .formed kat one end of thesleeveand adapted to mate restricting movement of the jacketto an axialdirection on the *sleeve when the pin is within the groove, said pin"being disposed. beyond vthe end of the jacket Whenthe jacket is movedagainst the bias of the springjtovexpose the `terminal and adapted tobear against the 'end of the jacket kto hold it in va retracted positionwhen the pin is y displaced radially from thel groove.

' References Cited in the file of this patent UNITED vvSTATES PATENTS

1. IN A CONNECTOR FOR ELECTRIC CABLES SAID CONNECTOR HAVING ANINSULATING JACKET, THE IMPROVEMENT COMPRISING A CONDUCTIVE SLEEVEDISPOSED WITHIN SAID JACKET AND ADAPTED TO RECEIVE A CABLE END, A SPLITIN THE WALL OF SAID SLEEVE ENABLING SAID SLEEVE TO BE COMPRESSED ABOUTTHE CABLE END, A SPLIT RING DISPOSED WITHIN SAID SLEEVE IN THE REGION OFTHE SPLIT, AND AN OUTER RING POSITIONED CONCENTRICALLY ABOUT SAID SLEVEIN THE REGION OF THE SPLIT FOR COMPRESSING SAID SLEEVE AND SPLIT RING ONSAID CABLE END TO ESTABLISH ELECTRICAL CONTACT THEREWITH.